Bending-machine.



J. GRADY.

BENDING MACHINE.

APPLICATION FILED MAR.27, 1911.

Patented May 6, 1913.

3 SHEETS-SHEET l.

o m H M Y B WITNESSES:

- \A TI'ORNEY J. GRADY.

BENDING MACHINE.

APPLIGATION FILED 141111.27, 1911.

Patented May 6, 1913.

3 SHEETSSHEET 2.

' INVE/V TOR WITNESSES:

' l1 TTOR/VEY J. GRADY.

BENDING MACHINE.

APPLICATION FILED MAR. 27, 1911.

1,061,067, Patented May 6, 1913.

3 SHEETS-SHEET 3.

WITNESSES: IAN/EN TOR UNITED STATES PATENT OFFICE.

- JAMES'GRADY, OF NEW YORK, N. Y., ASSIGNOR TO THE COLUMBIA. MACHINE WORKS &

MALLEABLE IRON 00., OF BROOKLYN, NEW YORK, A CORPORATION OF NEW YORK.

BENDING-MACHINE.

To all whom it may concern.

Be it known that I, JAMES GRADY, a citizen of the United States, residing in the borough of Brooklyn, in the county of Kings, city and State ofNew York, have invented an Improvement in Bending-Machines, of which the following is a specification. 7

In the pistons of air compressors and other mechanical devices or machines, metal rings are used inside the piston leathers or packings to get the same pressed outward against the inner walls of the air compressor cylinder. These rings are formed from pipe or tubular bodies cut up into sections of the desired diameter and thickness and they are expensive to make.

The object of my invention is to lessen thecost of manufacture, the time consumed in making the rings, and to improve the product.

In carrying out my invention, I take a single or composite rod member rolled of the desired cross section and cut the same up into suitable and approved lengths and preferably heat the same, and I employ a circular and revoluble mandrel having a periph eral groove adapted 'to receive the rod lengths, with similar faces toward one another. The mandrel is mounted in a lathe or other suitable machine and I provide means for advancing the rod and rolling the same around the mandrel in the groove thereof while a circular or ring form is being, imparted thereto. I also provide an adjustable and removable pressure roller or plurality of such rollers adapted to press against the periphery of the mug form and mandrel for rolling and simultaneously pressing the ring form compactly into the groove of the mandrel, imparting a finished form thereto. I may also provide the mandrel with suitable means for engaging the advancing ends of the rod lengths and holding the same against longitudinal stress and with other means for holding the rod length at the advancing ends in the grooves and a pressure roller for com leting the rolling operation, all of which is hereinafter more particularly described.

In the drawing Figure 1 is an end elevation representing the devices of my invention in their initial position of operation.

Fig. 2 is a side elevation of the same parts Specification of Letters Patent.

Application filed March 27, 1911.

Serial No. 617,014.

later on in their movement. Fig. 3 is an end elevation representin the finishing act upon the ring form and ig. 4 is a vertical section and partial elevation of the piston Patented May 6, 1913.

rod and the walls of an air com ressor or other cylinder showing the position of the finished ring form and its relation to the other parts. Fig. 5 shows the notched ad'-' vancing end of the rod. Fig. 6 is an elevation and Fig. 7 a vertical central section and elevation through Fig. 6 representing a form of my invention. Fig. 8 is a plan and Fig. 9 a cross section of a modified form of ring.

Similar letters and numerals of reference throughout the drawings represent similar parts.

The circular and revoluble mandrel comprises suitable disks ab, of which a is prefother words, the disks together. These disks are preferably connected together and mounted upon a head stock a and lathe arbor c by a series of tap bolts 2 in spaced apart relation. The mandrel is peripherally grooved at 3, a part of the groove being in each disk by preference. The mandrel is provided wit-h a transverse peripheral key d which is preferably slightly tapering so as to prevent the same being'pulled in a radial direction out of the mandrel. I also provide a yoke bar e adapted to straddle the periphery of both disks a b, and a yoke bar pine is adapted to ends of the yoke-bar and t rough a hole in the mandrel, or in other words, two alined holes'in the respective disks, and this yoke bar is located adjacent to the key d,see particularly Fig. 1.

The rod to be bent is shown at f. As-

illustrated, this rod is a flat stri with a semi-circular bead on one side a ong one edge. This is simply a form of rod advantageous to be bent u into a ring form. In the manufacture of t e rod, and as hereinbefore stated, the form in cross section is given to the rod by prior treatment between suitable rollers and the same is cut up into suitable and predetermined lengths according to I ass through the metal rings that are employed in connection with pistons of various characters.

the size of the ring to be formed and .the mandrel on which it is formed. The respective ends are preferably tapered so as to overlap one another as is usual with the The ressure roller employed by me in connection with the mandrel is adjustable and movable and as shown generally comprises a head 9 and auxiliary head 9 the necessary part of my invention.

Referring particularly to Fig. 1, the rod 1'' is illustrated in its initial position with reference to my improved mandrel. In other words, the advancing end of the rod f has been notched to be passed over the key cl. (See Fig. 5.) This notch is made throu h a semi-circular head of the rod and t e groove in the mandrel is preferably made semi-circular to receive this beadythe flat strip portion of the rod preferably overlying the face or periphery of the -mandrel,- therefore the rod is in osition to be pulled upon by the rotation of the mandrel and in order that the rod in this position may not jump away or pull over the key d, I employ the yoke bar 6 and pin 6 hereinbefore dc scribed. This bar is placed over the rod close to the key d; the pin 2 being removable and theinner surface of the yoke-bar touching the outer face-of the flat strip of the rod so that by these devices the pulling stress and the holding down function are performed as the rod is connected to the mandrel and while the rod is being turned. Of course the yoke bar cannot be retained on the mandrel for a complete revolution, otherwise the end of the rod f would overlap the outer surface of the yoke bar, and this yoke bar must be removed by pulling out its in and laying the two parts aside before tlie rotation of the mandrel is completed.

In the operation of rolling the rod f the parts are connected as shown in Fig. 1 and hereinbefore described, and the mandrel started in its rotation. As soon as the yoke bar passes by the location of the roller 1' the mandrel is stopped momentarily and the roller brought up into position to bear with force upon the outer face of the rod f and the rotation of the mandrel continued. The mandrel is again stopped before the yoke bar will reach the free end of the rod 1 and said yoke bar and its pin are then removed from the. mandrel, the rotation of which is thereafter continued, with the pressure of the roller 2' against the rod for.

any appreciable time desired until the rod f is completely and fully rolled in the groove of the mandrel and a permanent form imparted thereto. After this permanent form 1s unparted to the pre ared rod section f and the ring formed, this ring may be removed m any manner desired, but preferably by taking off the outer face or disk a which is accomplished by loosening up the tap bolts 2 a sufficient distance so that they are withdrawn from the disk (1 and one can -also spring the ring out of the groove of the mandrel and so move it overthe periphery of the disk a.

In Fig. 4, 6 represents the inner surface of the walls of the air'compressor itself. The piston is shown as composed of two disk members 7 8 connected together and to the plston rod 9 in any usual or well known manner.

10 represents the packing of L-form in cross section and f is the circular pressure ring formed by rolling the rod 7 around the mandrel in a position in which the outer fiat face of the same bears against the portion of the packing which lies parallel with the inner circular walls and in which a part of the semi-circular bead fits the curved portion of said packing; the spring function of said rod tending to push the packing out against the inner surface of the cylinder and to hold the same in said osition, yielding when the piston is moving in an opposite direction to permit the fluidto pass by the packing ring 10.

The device of my invention may of any diameter and any cross sectional area, and the same is adapted for use with any usual form of piston member for an air compressor or any similar mechanical device or machine, consequently my invention is not limited in its application.

.W'hile I have shown a single roller 2' adapted to be brought up to the mandrel against the rod to be rolled to force the same into the groove, I do not limit my invention to the use of one roller as several or a series may be employed spaced around therein I do not employ the key d or the" yoke e and pin 0 I provide a series of rollers i spaced around the mandrel a and all adapted to press the rod member f into the groove of the mandrel a in rolling the or piston leather be made same into a ring. In this connection I have shown the rollers 2' each mounted in a yoke 11 with a screw-stem 12 passing through a ring frame 70 upon a base 10 and each screwstem 12 is provided with a lock nut 13 for fastening the stem of the roller after adjustment. I have also shown a pair of feeding or advancing rollers Z Z and the frame is notched for the rod f, as it will be necessary to employ some means for feeding the rod member f throughout its length.

In Figs. 8 and 9 Ihave shown a modified form of ring in which the same is formed from a Wire 15 and a strip of sheet metal 14, one edge of which is rolled around the wire, the completed form agreeing in cross section with the solid rod Fig. 1.

I claimas my invention:

1. In a rod bending device and in combi nation a suitable revoluble support, a circular and revoluble mandrel having a peripheral groove, a device for engaging the initial or advancing end of the rod with the mandrel, a removable device for initially holding the end of the rod in the groove of the mandrel and a roller device for pressing the rod into the groove of the mandrel while being bent through continuous revolutions.

2. A forming mandrel comprising the disks a b with a peripheral groove in the adjacent edges of each disk, together forming a groove of predetermined form, a head stock and lathe arbor and tap bolts for simultaneously connecting the said head stock and disks removably together, a key of tapering form adapted to be seated in a tapering aperture across the periphery of the disks forming the mandrel and across said groove, :1 yoke-bar adapted to straddle the said disks at their peripheries and adjacent to said key, and a pin adapted to pass through the free ends of the yoke-bar and through apertures in the disks to hold the yoke-bar in a removable and replaceable JAMES GRADY.

Witnessesi ARTHUR H. SERRELL, HAROLD SERRELL. 

